Swing A/C milling heads are mounted on the ram's end plane and installed with high speed electric spindle driven by synchronous motor. A/C axises are supported by high precision rotary table bearing, driven by high precision OTT eliminating clearances worm and worm gear, detected by high precision angle encoder closed loop position and equipped with clamping device. Max. torque is 4000Nm and max. clamping force moment is 7000Nm on A/C axis.